First of all this is a very common problem, for more details see this post http://www.yiiframework.com/forum/index.php/topic/52052-upload-file-with-any-charset/
First of all this is a very common problem, for more details see this post http://www.yiiframework.com/forum/index.php/topic/52052-upload-file-with-any-charset/
There are cases that you want to validate the file format, size, extension etc but how to do that without submit the form ?